Choosing and mounting replacement sockets
Always socket replacement chips. Machine-pin SIP strips are best, since they leave the component side open and can be soldered from the top. Open-frame sockets that grip the leg on both sides also work; mount them slightly above the board so they can be soldered from the top if a plated-through hole cracks.
Systems
Related tips
- System 7 CPU ROM sockets
- Installing a single-EPROM adapter in the CPU socket
- Lockups and locked-on coils from worn chip sockets
- Settings behave strangely on a replacement CPU: use the later adjustment sheet
- Replacement CPU board: game won't start though tests pass: DIP switches reversed
- Solenoid fuse F2 blows at power-up as every coil fires: CPU blanking circuit
- System 6 won't boot and fails the 5101 RAM test even after replacing it: bad 5101 stock
- Boots into audit mode every power-up with good batteries: bad 5101 RAM
Source: Repairing Williams System 3 to System 7 Pinball 1977 to 1984, Part One, Clay Harrell (pinrepair.com)